1. Field of the Invention
The present invention relates, in general, to a microwave oven and a method of controlling the same and, more particularly, to a microwave oven and a method of controlling the same, which prevents a generation of sparks resulting from a concentration of microwaves in a cooking cavity by a high frequency oscillation.
2. Description of the Related Art
Generally, a microwave oven is an apparatus to cook food using microwaves provided to a cooking cavity from a microwave oven.
Microwave ovens have been provided with heaters as a heating source in the cooking cavity, as well as a magnetron to irradiate the microwaves, and perform grill cooking by the heaters and combination cooking by the heaters and the magnetron.
In some models of microwave ovens, the heaters are rotatably disposed. Motors are disposed outside the cooking cavity such that rotating shafts of the motors penetrate a back wall of the cooking cavity, and are assembled to rotating members to which the heaters are attached.
Accordingly, when the grill cooking or the combination cooking is performed, the heaters are operated after the heaters reach respective predetermined heating positions by being rotated by the motors in some direction and when the grill cooking or the combination cooking is terminated, the heaters return to respective initial positions thereof by being rotated in a reverse direction.
However, when the combination cooking is performed by the conventional microwave oven, an operation of the magnetron and the rotation of the heaters are simultaneously performed. Accordingly, when the heaters are, respectively, rotated by the motors to reach the predetermined heating positions while the microwaves generated from the magnetron are radiated into the cooking cavity, the microwaves are concentrated into a space between the heaters and the rotating members or between the rotating shafts of the motors and the back wall of the cooking cavity, so sparks may occur in areas of a microwave concentration.